drush site-upgrade --core-only @example.d7 fails both on 5.x and 4.x

Can't reproduce the OP with 5.x, but 5.x fails at a later point for me:

Drupal site already exists at [...]/dev7.  Would you like to:
 [0]  :  Cancel
 [1]  :  Delete the existing site and start over.
 [2]  :  Re-use the existing code, re-import the database from the source site and run updatedb again.

1
Install location [...]/dev7 already exists. Do you want to overwrite it? (y/n):
y
Project drupal (7.4) downloaded to [...]/dev7.                         [success]

Project drupal contains:                                                                                       [success]

 - 3 profiles: testing, standard, minimal
 - 4 themes: stark, seven, garland, bartik
 - 47 modules: [...]

You will destroy data from drupal7 and replace with data from drupal6.

You might want to make a backup first, using the sql-dump command.

Do you really want to continue? (y/n): y
Table 'drupal7.access' doesn't exist                                                 [warning]

query: SELECT 1 FROM access WHERE type = 'host' AND LOWER('127.0.0.1') LIKE LOWER(mask)
AND status = 0 LIMIT 0, 1 database.mysqli.inc:134
Table 'drupal7.cache' doesn't exist                                                  [warning]

query: SELECT data, created, headers, expire, serialized FROM cache WHERE cid = 'variables'
database.mysqli.inc:134
Table 'drupal7.variable' doesn't exist                                               [warning]

query: SELECT * FROM variable database.mysqli.inc:134
Table 'drupal7.cache' doesn't exist                                                  [warning]

query: UPDATE cache SET data = '', created = 1311533255, expire = 0, headers = '',
serialized = 0 WHERE cid = 'variables' database.mysqli.inc:134
Table 'drupal7.system' doesn't exist                                                 [warning]

query: SELECT name, filename, throttle FROM system WHERE type = 'module' AND status = 1 AND
bootstrap = 1 ORDER BY weight ASC, filename ASC database.mysqli.inc:134
Table 'drupal7.url_alias' doesn't exist                                              [warning]

query: SELECT COUNT(pid) FROM url_alias database.mysqli.inc:134
Drush command terminated abnormally due to an unrecoverable error.                                               [error]

Error: Call to undefined function filter_xss() in [...]\dev\includes\common.inc, line 655

Fatal error: Call to undefined function filter_xss() in [...]\dev\includes\common.inc on line 655

Call Stack:
    0.0006     383448   1. {main}() [...]\scripts\drush\drush.php:0
    0.7415    2940168   2. drush_main() [...]\scripts\drush\drush.php:14
    1.2866    6345376   3. drush_bootstrap_to_phase() [...]\scripts\drush\drush.php:70
    1.3808    8430232   4. drush_bootstrap() [...]\scripts\drush\includes\bootstrap.inc:305
    1.3809    8430944   5. _drush_bootstrap_drupal_full() [...]\scripts\drush\includes\bootstrap.inc:189
    1.3809    8471984   6. drupal_bootstrap() [...]\scripts\drush\includes\bootstrap.inc:835
    1.3922    8682800   7. _drupal_bootstrap() [...]\dev\includes\bootstrap.inc:1109
    1.3924    8682800   8. _drupal_bootstrap_full() [...]\dev\includes\bootstrap.inc:1202
    1.4258   11211616   9. module_load_all() [...]\dev\includes\common.inc:2673
    1.4258   11211680  10. module_list() [...]\dev\includes\module.inc:12
    1.4258   11211904  11. db_query() [...]\dev\includes\module.inc:63
    1.4259   11212296  12. _db_query() [...]\dev\includes\database.mysql-common.inc:41
    1.4263   11213248  13. trigger_error() [...]\dev\includes\database.mysqli.inc:134
    1.4263   11214360  14. drupal_error_handler() [...]\dev\includes\common.inc:134

Observations:

- it seems to attempt to bootstrap the old D6 site somehow with the new/empty database (not sure how that is actually possible...?)

- the D7 database is still empty.

- settings.php in the fresh D7 site contains a D6 style $db_url string appended to the end, which contains the new/D7 db credentials (probably intended to be replaced by Drupal core upgrade)

1. It does do that. It can do so because the new DB has not been upgraded. In other words, it is still a D6 database and we are merely running on a copy of the real source DB.

2. The new DB should not be empty if the sql-sync succeeds. It seems like yours failed, but without a --verbose log I can't be sure.

3. Correct about D7 upgrade appending $databases.

error: no database record could be found for @self

For the above error we cleared the .drush/cache and it got past the error.

I am not sure that would help with your issue.

This issue was marked closed (won't fix) because Drush has moved to Github.

If desired, you may copy this bug to our Github project and then post a link here to the new issue. Please also change the status of this issue to closed (duplicate).

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